NEW YORK (Reuters Health) - The use of braces to correct excessive curvature of the spine (scoliosis) in adolescents is a subject of ongoing debate and a new review of the medical literature does little to resolve the matter.

Although there is some evidence that adolescents with scoliosis may benefit from wearing hard or elastic braces to correct spinal curvature, research thus far has failed to prove definitively that bracing works, the investigators conclude.

The evidence for bracing is weak, as is the evidence of any long-term benefits of bracing, Dr. Stefano Negrini of the Italian Scientific Spine Institute of Milan, Italy, and colleagues report in the latest issue of The Cochrane Library, a publication of the Cochrane Collaboration, an international organization that evaluates medical research.

Negrini and his team searched the medical literature for studies comparing braces with no treatment, other treatment, surgery, and different types of braces. From a pool of 1,285 titles, the researchers read 128 full texts, and found only 2 that fit their criteria.

One study involved 286 girls; some wore a brace, some received electrical stimulation, and some received no treatment at all, for up to 4 years.

This study found evidence that bracing was more effective than observation (wait-and-see) or electrical stimulation. At three years, the success rates were 80 percent for bracing, 46 percent for observation and 39 percent for electrical stimulation. At four years, the success rates were 74 percent, 34 percent and 33 percent, respectively. However, over the long term, formerly braced patients reverted back to their pre-treatment curvatures.

The other study compared the efficacy of rigid versus elastic braces in 43 girls over 45 months. This study found evidence that rigid braces were more effective than elastic braces.

However, both studies, the researchers emphasize, constituted very "low quality evidence" in favor of using braces.

Despite the lack of strong evidence, Negrini told the Health Behavior News Service, that his clinic often prescribes braces in conjunction with exercises for patients with scoliosis.

"We are aware of the very good results it is possible to obtain with high-quality bracing and making sure there is good patient compliance with wearing the brace," Negrini said.

Dr. John Dormans, chief of orthopedic surgery at the Children's Hospital of Philadelphia and president of the Pediatric Orthopedic Society of North America, also favors bracing.

"If you polled the orthopedists who treat the vast majority of patients with adolescent idiopathic scoliosis, the overwhelming opinion would be that bracing is effective, that it does alter the natural history of the disease," Dormans said.

But getting teenagers to wear the brace for an adequate number of hours each day is a big issue. "The efficacy of bracing depends on two main factors: efficacy of the brace itself and compliance," Negrini wrote in an email to Reuters Health.

Questions about the effectiveness of bracing for adolescent scoliosis might soon be answered by more definitive research: a five-year, multimillion-dollar study funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases is currently under way.